TY - JOUR

T1 - RNF4 is required for DNA double-strand break repair in vivo

AU - Vyas, R

AU - Kumar, R

AU - Clermont, F

AU - Helfricht, A

AU - Kalev, P

AU - Sotiropoulou, P

AU - Hendriks, I A

AU - Radaelli, E

AU - Hochepied, T

AU - Blanpain, C

AU - Sablina, A

AU - van Attikum, H

AU - Olsen, J V

AU - Jochemsen, A G

AU - Vertegaal, A C O

AU - Marine, J-C

PY - 2013/3

Y1 - 2013/3

N2 - Unrepaired DNA double-strand breaks (DSBs) cause genetic instability that leads to malignant transformation or cell death. Cells respond to DSBs with the ordered recruitment of signaling and repair proteins to the sites of DNA lesions. Coordinated protein SUMOylation and ubiquitylation have crucial roles in regulating the dynamic assembly of protein complexes at these sites. However, how SUMOylation influences protein ubiquitylation at DSBs is poorly understood. We show herein that Rnf4, an E3 ubiquitin ligase that targets SUMO-modified proteins, accumulates in DSB repair foci and is required for both homologous recombination (HR) and non-homologous end joining repair. To establish a link between Rnf4 and the DNA damage response (DDR) in vivo, we generated an Rnf4 allelic series in mice. We show that Rnf4-deficiency causes persistent ionizing radiation-induced DNA damage and signaling, and that Rnf4-deficient cells and mice exhibit increased sensitivity to genotoxic stress. Mechanistically, we show that Rnf4 targets SUMOylated MDC1 and SUMOylated BRCA1, and is required for the loading of Rad51, an enzyme required for HR repair, onto sites of DNA damage. Similarly to inactivating mutations in other key regulators of HR repair, Rnf4 deficiency leads to age-dependent impairment in spermatogenesis. These findings identify Rnf4 as a critical component of the DDR in vivo and support the possibility that Rnf4 controls protein localization at DNA damage sites by integrating SUMOylation and ubiquitylation events.

AB - Unrepaired DNA double-strand breaks (DSBs) cause genetic instability that leads to malignant transformation or cell death. Cells respond to DSBs with the ordered recruitment of signaling and repair proteins to the sites of DNA lesions. Coordinated protein SUMOylation and ubiquitylation have crucial roles in regulating the dynamic assembly of protein complexes at these sites. However, how SUMOylation influences protein ubiquitylation at DSBs is poorly understood. We show herein that Rnf4, an E3 ubiquitin ligase that targets SUMO-modified proteins, accumulates in DSB repair foci and is required for both homologous recombination (HR) and non-homologous end joining repair. To establish a link between Rnf4 and the DNA damage response (DDR) in vivo, we generated an Rnf4 allelic series in mice. We show that Rnf4-deficiency causes persistent ionizing radiation-induced DNA damage and signaling, and that Rnf4-deficient cells and mice exhibit increased sensitivity to genotoxic stress. Mechanistically, we show that Rnf4 targets SUMOylated MDC1 and SUMOylated BRCA1, and is required for the loading of Rad51, an enzyme required for HR repair, onto sites of DNA damage. Similarly to inactivating mutations in other key regulators of HR repair, Rnf4 deficiency leads to age-dependent impairment in spermatogenesis. These findings identify Rnf4 as a critical component of the DDR in vivo and support the possibility that Rnf4 controls protein localization at DNA damage sites by integrating SUMOylation and ubiquitylation events.

KW - Alleles

KW - Animals

KW - BRCA1 Protein

KW - Cell Line

KW - DNA Breaks, Double-Stranded

KW - DNA Repair

KW - Genotype

KW - Intracellular Signaling Peptides and Proteins

KW - Mice

KW - Mice, Transgenic

KW - Nuclear Proteins

KW - Rad51 Recombinase

KW - Radiation, Ionizing

KW - Sumoylation

KW - Transcription Factors

KW - Ubiquitination

U2 - 10.1038/cdd.2012.145

DO - 10.1038/cdd.2012.145

M3 - Journal article

C2 - 23197296

VL - 20

SP - 490

EP - 502

JO - Cell Differentiation and Development

JF - Cell Differentiation and Development

SN - 1350-9047

IS - 3

ER -